Fluid-flow meter and the like



Oct. 3, 1944. c STOKOE' 2,359,592

FLUID-FLOW METER AND THHLIKE Filed Sept. 8, 1942 #9 a, t I

W 2 q I 'IMIIIIIIIIIIIIIAEIIIIIII' Patented Oct. 3, 1944 Charles Leslie Stokoe, Wallsend-onrtlyne, England Application September 8.1942, Serial No. 457,665 In Great Britain October 26', 1 941 8 Claims.

My invention relates to improvements in fluidfiow meters and thelike and has-for its object to provide an improved flow meter or flow indicator-of the kind in'which the action ofthe moving fluid on a pivoted flap member located in the path of said fluid rotates a spindle to which is attached a flow-indicating pointer and/or flowrecording pen and/or a tappet' or the-liketo-bring into operation alarm or-control on predetermined alteration in flow through th pipe of which said flow meter may form apart.

According to my present invention a fluid-flow meter of the kind referred to differ from the prior art in that the spindle on which the flap is pivoted is not carried through the walls-of the meter to transmit motion to an external pointer. My invention relates to the means I employ to transmit the angular movement of the flap to what I term in this specification the operating spindle, this being located in a chamber external to the meter bore, the connection between this spindle and. the flap member being a connecting rod or link inconjunction with a crank. My invention also relates to the combination of this link with the means I employ to prevent leakage past the aperture through which the operating spindle project to the atmosphere. Other features of my invention includ the means for testing the freedom of movement of the flap member without putting undue strain on the operating spindle and connections. I also describe and illustrate the means'I adopt with a view .to ease-of construction, simplicity of design, the special shape of the flap, inlet bush and outlet guide plate for improved flow indication; also one means I adopt to equalize approximately the movements of the flow-indicating pointer when the outlet plate is omitted to allow-of increased flow indicating capacity. I also describe one means I adopt for recording the variations of flow over a period of time by means of a pen or pencil attached-to a band or cord laid round two pulleys. Th meansof absorbing the end-thrust on the operating spindle due to high internal fluid pressure is describedand also how I arrange for the adjustable tappet to clear the outer hearing of said operating spindle and the means for showing by a pointer over a graduated dial at what point on the meter dial the alarm or control will come into operation. The special crank disc forrelieving strain fromthe operating spindle due to the pull of the I'm-k or connecting. rod because the disc carries the weight of such link and provisiion for access to the pin of saidtconnectin'g rod for assembly or overhaul are described also the means of assembly of the bush, flap member and flap spindle bracket together with the outlet plate prior to insertion in the bore of the meter. Provision isalso made for arranging the meter to be suitable for any specified direction'of flow, for example, to the right, to the-left, or upward flow.

In order to make my invention clear, reterence is made to the accompanying drawing wherein:

Fig. '1- is a sectional elevation of my improved meter."

Fig.2 is a cross section of my improved meter;

Fig. 3 shows a section of .thebody of the meter wherein is locatedthe bush which carries the flap spindle bearings and whic-halse iormsaseat for said flap, the bush sides shown in section being utilised to guide the flow of the fluid and assist streamline flow past the flap,

Fig. 4 shows details of the operating spindle and connection tothe crank disc also the arrangement of the tappet attachment to the flow indicating pointer, to clear the bridge for overhaul.

Fig. 5 shows how the operating spindle maybe constructed for cases where the internal fluid pressure is-low.

Fig. 6' shows the relative positions of the tappet indicator pointer reference to the flow-me dicating pointer, this being adjustable for predetermined alteration of flow, meter in serv ice.

Fig. 7- show alternate fulcrum attachment of the link rod to that illustrated in Fig. -1 inorder to open out the close reading towards the full open positions of the flap when the outlet plate is omitted in order to provide greater flow indicating capacity for that size-of meter.

Fig. 8" shows one arrangement of pen movementfor recording the-rateof flow-over a period of time on a movin chart, on clock drum. Various forms of flow meters and flow indicators have been devised on the swinging flap principle,-

one type employing link-motion to operate a spindle projecting from an upper-chamber :for the purpose of recording the rate of fiowpnca 'moving chart. Owing to the difiiculty-of the spindle aperture fluid-tight the diameter oi the spindle was of necessity too small tor "the purposes set forth in this present-specification. a packed gland causes too muchfriction. when screwed up the necessary arnountto: prevent-mu;- due leakage. Leakage past thespindle aperture of any meter can be a serious commereialidrawback. In my previous-constructions otzflowrmetersand flow indicatOrs with alarm and the meter.

strength for the purpose without the necessity of boring the walls of the meter body for the reception of bearings and also as previously stated to allow the flap member to be assembled complete with the guide bush and the outlet plate (when fitted) before insertion in the meter bore.

A further object of my present invention is the location of the flow indicating, flow recording 7 and alarm or control attachments above (or clear)v of the'meter body so that it can b under ,obs'ervationgwithout obstruction. A desirable featurein a flowmeter or flow indicator is the ability for testing thejfreedom of the internal member whilst in service, hence the purpose of thetesting wheel illustrated in Fig. 2. r p

In Fig. 1 the meter body a is bored uniformly the whole length (to the diameter indicated). b isjthe flap member pivoted on spindle c supported by bearing bracket (1, the bracket being bolted to the bush e which also forms a seat for the flap in the no-flow position. The sides of the bush Fig. 3 at f form guides to assist streamline flow towards the flap member. My tests denote that the segmental open sides at g, g, pro duce armore steady flow Vindication than when closed, the outlet plate It being, approximately the same width as the flap which it will be observed is rectangular in shape and does not project quite tothe bottom of the central'rectangular opening 7' in the bush. The Width of opening :i may be approximately half the diameter of meter bore. The bush e is made interchangeable end for end in thebody of meter use that if desired ,thedirectionof flow may be tothe right, as seen from the observer. For the same reason the :cover' it may be'made reversible, although I may provide alternate means for turning round-the face or the ,meter dial and connected parts to face. anydirection by means of the swivel union m in the connecting rod or link 11.. The rod n is connected at one end to disc r and at its lower end to a crank pin q, attached to the flap as the intensity of flow increases. This rotates the crank disc T which disc isfulcrumed between the ends of a fixed spindl 'a glocated in the side of the chamber Z. 'I'rhe'rotation of crank disc 1 is due to internal fluid pressure on the projecting area of the operating spindle is absorbed by the ball thrust bearing g supported by the bridge 71 attached to the cover a The tappet gear by which the alarm or control mechanism is brought into action on predetermined alteration of flow through the meter, i carried by a bracket i secured to the pointer 0 and projects clear of the bridge h This bracket carries a graduated dial plate 7' over which a pointer k may be moved round by hand to any desired mark representing 7 the equivalent flow marking on the main flow indicating dial d at which the alarm or control is to be operated by the projecting tappet Z The compression spring m held by the nut n thread on shaft fixed to the bracket 12 keepsthe pointer located. The projectingtappet Z may be used for example in the case of mechanical alarm or control to tilt up a lever operated valve in connection with a source of compressed air supply to sound a whistle or operate a servo-motor'or the like. In the case of electricalalarm or control the tappet may tilt up an insulated lever in connection with make or break contacts, to sound a .bell or horn or tooperatea control switch to stop or start. a motor or the like. ;.Referring to Fig. 2 it will be seenthat the freedom of the flap movement may be tested by means of the push hand wheel 0 attached to the rod 11 which is provided at. its inner end with a clutch to engage a corresponding slot 1 in the end of the flap spindle c. Leakagepast the rod aperture is preventedin the normal position bythe reaction of the compression spring s threaded 'on the external portion of, the rod which presses a resilient (such as leather) washer r onto the inner face of the bearing s and which normally provides for the push handleto be out with the clutch clear of the flap spindle. 1 The testingof the flap member of course tests the various moving members in connection'therewith. i

Fig. 5 shows a simplified arrangement of the operating spindle for cases where the internal fluid pressure is very low and the external thrust bearing ;not so essential. Herethe operating spindle is continuous and combines the crank disc r to which it is attached. With this arrangement I provide for the resilient washers or washer tobe pressed up against the'inner .face of the bearing in cover a byacompression spring t axial to and at the .back end of, said "spindle 'the thrust being transmitted by a ball which transmitted to the operating spindle t by the crank pin it engaging in slot formed in disc '0 attached to the operatingspindle. A compression spring w onthe operating spindle gives axial ,p're'ssure to the sliding collar ac faced by an anti- Ifriction ring 11 which in turn presses the resilient washer (or washers such as leather) 2 onto the inner face of the bearing formed in the cover a ito :prevent leakage past the spindle aperture.

The operating spindle t carries a boss b which for convenience of assembly may be bolted in -halves, to which is attached the flow indicating the operating spindle may beielt. End thrust presses on the end of the operating spindle with minimum friction. The sliding collar :0 shown in Fig. 4 is now replaced by a collar y rigidly attached to the operating spindle. Access to the connecting rodtop pin 1)? for ease of assembly and overhaul is by way or the opening in the wall of the chamber l. The opening u with cover 0 opposite the pin b permits removal of the connecting rod 1; fromthe crank disc'r.

Fig. 8 shows one meansI adopt for recording the rate of flow over a period of time. Th pen .w attached to a band or'cord laid over the pulleys :ri' and 1 on their respective spindles andthe pen rises 'or falls'in accordance with the variations of flow'through the meter. Th'e c'hart is suitably ruled and rotates with the usualclock typ of drum. With theoutlet plateco'rr'ectly at a instead of at q in Fig. 1. Without this feature the angular movement of the flap member is at first too fast and towards the full flow position too slow to give a good graph. It will be seen that when .the lower fulcrum is located on the centre line and the upper fulcrum located at say I) as in Fig. 1 the flow indicating pointer will move through a given angle more slowly than the flap member at first and more quickly than the flap member towards the full flow position.

The correct eccentricity of the contour of the outlet plate in order to give a straight line graph is so important that the manner in which the parts are constructed whereby the outlet plate together with flap member may be assembled onto the bush before insertion in th bore of the meter forms, an important feature of my invention. The contour of the outlet plate is obtained from actual flow test on what may be termed a standard meter for any given size so as to enable new meters to .be manufactured to the same dimensions thereby rendering unnecessary actual flow test on each meter. I also provide for more accurate flow indication by prolonging the tip of the flap as shown at d in Fig. 1 so that the issuing fluid will not impinge on the weighted portion of the flap member at e I previously referred to provision for making the meter suitable for say flow to the right, to the left, or upward flow. Referring to Fig. 1 it will be observed that the flow is to the left but can be arranged for flow to the right by reversing the bush e end for end and reversing the cover is likewise, or as before mentioned turning round the external chamber I and cover It provided the swivel joint m is included. For upward flow the external chamber would then be horizontal but th flow indicator dial and recording gear can be arranged to lie in the vertical plane.

It is obvious that the details of my flow meter could be modified without departing from the nature of my invention.

Havin now particularly described and ascertained the nature of my said invention, and in what manner the same is to be performed, I declare that what I claim is:

1. A fluid flow meter or the like comprising, in combination, a conduit having fluid flow bore and having a pivotally mounted flap member mounted therein, a meter casing mounted upon said conduit having a fluid-tight connection therewith, a crank disk and link mechanism mounted in said casing and connected with said flap member, an operating spindle for said crank disk extending out through one wall of said casing, means for testing the freedom of said flap member from outside of said casing, means for rendering the aperture through which said last named means passes fluid-tight, means connected to said spindle for indicating the rate of flow over a period of time, means for inducing a streamline flow past said flap member, and means for positioning the flow indicating means to any desired position with respect to the flap member, as desired.

2. A fluid-flow meter or the like as set forth in claim 1, including means whereby the aperture through which the operating spindle projects to atmosphere is rendered fluid-tight, said means including a spring and a resilient washer pressed by said spring against the inner wall of the casing through which the spindle projects.

3. A fluid-flow meter or the like as set forth in claim 1, including means whereby end thrust on said operating spindle due to internal fluidpressure is absorbed by an external thrust bearing forming a stop for the projecting end of the spindle, said spindle having a spring-pressed antifriction collar and adjacent-resilient-washer in said casing.

4. A fluid-flow meter or the like as set forth in claim 1, wherein the means for inducing a stream-line flow through the conduit include an inlet guide-bush, having two vertical walls which form a seat for the flap face in the no-flow position, said vertical walls bounding a central rectangular shaped aperture of an approximate width of half the diameter of the path of fluid flow, the segmental shaped openings at outer sides of said vertical walls forming a direct passage for a portion of the fluid-flow past the flap member.

5. A fluid-flow meter or the like as set forth in claim 1, wherein the tip of flap face terminates short of the bottom of the path of fluid flow, said flap member having a Weighted portion behind the face of flap arranged to clear the efflux from below the tip of flap face.

6. A fluid-flow meter as set forth in claim 1, wherein the means for testing the freedom of movement of the flap member includes a rotatable road projecting through a fluid-tight aperture in the wall of the meter casing, said rod being provided with an internal clutch element adapted to coact with said flap member, said element being normally clear of said flap member.

'7. A fluid-flow meter as set forth in claim 1, including an outlet plate approximately the same width as the flap face and comprising a part thereof suitably curved with relation to the path of travel of the flap member, said means for inducing a streamline flow including an inlet bush, a flap spindle bearing bracket mounted directly on the said inlet bush and together forming a unit for convenient assembly in the fluid-flow bore of the conduit.

8. A fluid-flow meter as set forth in claim 1, in which said flow indicating means includes a dial, means for turning said dial relative to the meter casing, a link connected with said dial and arranged on the vertical center line of the casing, and a swivel coupling to facilitate such operation.

CHAS. L. STOKOE. 

